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| 1 | 基于撬棒并联动态电阻的自适应双馈风力发电机低电压穿越显示文摘当电网故障引起电压跌落时,为防止大装机容量风电场的风机脱网,双馈风力发电机(DFIG)多采用Crowbar电路来实现低电压穿越(LVRT)。传统Crowbar电路采用固定阻值的电阻,很难兼顾对转子电流和直流母线电压的抑制以及对Crowbar的投入工作时间的控制。针对传统Crowbar的不足提出了一种基于Crowbar并联动态电阻的双馈风力发电机低电压穿越方案,制定了该方案的自适应控制策略以及其阻值的整定方法。仿真分析不同跌落深度下所提方案的LVRT特性,并与改变IGBT的导通脉宽的变电阻Crowbar方案进行了比较,结果表明带并联动态电阻Crowbar方案的LVRT效果较好,不仅兼顾了对转子过电流和直流母线过电压的抑制,而且在电压深度跌落时可缩短Crowbar的投入时间,有利于系统电压的恢复。 | 张曼 姜惠兰 | 2014 | 电工技术学报2014，29，2： | 37 |
| 2 | 电压源换流器直流侧短路故障特性分析显示文摘电压源换流器直流侧发生故障时,其故障电压电流变化迅速,对系统造成了严重威胁。针对这一问题,从电力电子层面深入分析了电压源换流器直流侧短路故障中最为严重的两极短路故障过程。将故障过程分为3个阶段,推导了电容放电阶段直流电压、电流表达式,分析了不控整流初始阶段存在的两种情况,对不控整流稳态阶段提出了采用开关函数计算短路电流的方法。最后通过PSCAD/EMTDC环境下±10 kV直流线路两极短路故障模型的仿真计算,对理论分析进行了验证。研究结果表明,两极短路故障后电路的响应情况与短路阻抗大小相关,短路阻抗较小时需要直流断路器在极短的时间内切除故障,短路阻抗较大时则可以利用交流侧的保护装置对直流侧电压、电流进行动态监测,实现直流侧短路故障的后备保护。 | 胡竞竞 高一波 严玉婷 徐习东 | 2014 | 机电工程2014，31，4： | 24 |
| 3 | ZnO varistors with high voltage gradient and low leakage current by doping rare-earth oxide显示文摘The surge arrester of 1000 kV gas-insulated substation (GIS) needs ZnO varistor with high voltage gradient to effectively improve the potential distribution along ZnO varistor column inside the metal-oxide surge arresters. In this paper, the elec-trical and structural parameters of ZnO varistors are changed by doping with some rare-earth oxides, and the mechanism which leads these changes is discussed. When rare-earth oxide additives are added into ZnO varistors, the growing speed is slowed down due to the stabilization of the new spinel phases formed in the grain-boundary by rare-earth oxide additives, then the size of ZnO grains is smaller, and the voltage gradient of varistor increases obviously. By adding suitable amount of oxides of metal Co and Mn, the leakage current can be effectively decreased and the nonlinearity coefficient increased. The novel ZnO varistor samples sintered with the optimal additives have a voltage gradient of 492 V/mm, and the nonlinearity coefficient of 76, but their leakage currents are only 1 μA. | HE JinLiang HU Jun LIN YuanHua | 2008 | Science China(Technological Sciences)2008，51，6： | 21 |
| 4 | 高压电能表在智能电网中的应用研究显示文摘介绍了智能电网中的高级计量体系和需求侧管理的概念,结合传统高压电能计量装置的若干问题,分析了新型高压电能表的工作原理,提出了高压电能表应用于智能电网中配网计量的主要应用方案,并结合实际运行情况进行了应用分析。 | 胡永平 胡顺 徐芝贵 | 2010 | 水电能源科学2010，28，9： | 17 |
| 5 | 特高压输电线路直流融冰变流系统设计显示文摘随着特高压的推广,特高压输电线路的抗冰融冰正成为研究的热点。特高压输电线路由于线径粗、线路长,所需融冰电流与装置容量大,其电流融冰是一个研究的难点。针对特高压输电线路的特点提出了分段直流融冰方法,其将特高压输电线路分成若干段,选取重覆冰区的线路段设置直流融冰点与融冰短路点,可以有效减小融冰装置容量。针对特高压输电线路融冰所需直流融冰装置容量大特点,为了减小融冰装置网侧电流的谐波畸变率,采用24脉波整流变压器+多台整流器并联方式,可以有效减小直流融冰装置对网侧电源的干扰,并可减小输出直流电压纹波因数。最后对所设计的特高压输电线路直流融冰装置进行了仿真研究,采用24脉波整流变压器+多台整流器并联方式后,可以有效消除整流器引起的输入侧电流中5次和7次谐波电流,整流变压器输入侧电流低次谐波总畸变率仅为0.51%,输出直流电压脉波数为24,电压纹波因数仅为0.616。仿真结果证明了所设计特高压直流融冰装置的可行性与正确性。 | 陆佳政 朱思国 李波 方针 张红先 | 2014 | 电力系统保护与控制2014，42，11： | 17 |
| 6 | 基于dq锁相环的改进型光伏电站并网点电压跌落检测方法研究显示文摘快速准确检测出并网点电压不同类型的跌落故障是光伏电站实现低电压穿越的前提。针对电压负序分量导致基于dq锁相环的常规检测方法无法检测电压不对称跌落的问题,采用二阶广义积分法对电压进行相序分离,滤除负序分量让正序分量进入锁相环,实现对电压不对称跌落故障的检测。基于Matlab/Simulink搭建了仿真平台,仿真结果表明上述方法对多种类型的电压跌落故障有较高检测精度,验证了该方法的可行性。 | 罗劲松 王金梅 张小娥 | 2014 | 电测与仪表2014，51，5： | 15 |
| 7 | An approach to determining the local boundaries of voltage stability region with wind farms in power injection space显示文摘A new approach to determining the local boundaries of voltage stability region in power injection space (IVSR) for power system with wind farms is presented. It can be used for power system voltage stability analysis and on-line security assessment with considering the output uncertainty of the wind farms. Firstly, power flow tracing and double dispatching are used to determine the generators that are closely related to the wind farms, in order to balance the power fluctuations caused by the wind speed variation. Then, modal analysis is used to get the key generators to achieve an effective dimension reduction for IVSR. Finally, the forecasting output power (or wind speed) of wind farms is divided into several intervals. For each interval, the corresponding local IVSR boundaries can be calculated by the method based on small disturbance. Moreover, parallel process is used to accelerate the computing speed. The presented approach is validated by several power systems. It can be revealed that the approach can give the local IVSR boundaries at different wind speeds and has a good engineering application prospect. | MU YunFei & JIA HongJie Key Laboratory of Power System Simulation and Control of Ministry of Education, Tianjin University, Tianjin 300072, China | 2010 | Science China(Technological Sciences)2010，53，12： | 13 |
| 8 | 太阳电池最大功率恒压跟踪研究显示文摘通过单二极管五参数模型太阳电池的电流方程一阶导数,推导出光生电流变化而温度不变时的最大功率方程,并绘制最大功率曲线。太阳电池恒压跟踪(constant voltage tracking,CVT)的数学表述为dVm/dIm?0,即CVT仅是最大功率跟踪的特殊情况,通常情况下在最大功率曲线上仅是两个点。在CVT的点沿电流轴向两侧延伸,太阳电池最大功率点的电压变化不大而电流变化较大,就有了适用CVT的区间,其数学表述为dUm/dIm?0。该文给出了适用CVT的负载电流、光生电流区间,建议在不同的电流区间采用不同的恒定跟踪电压。从特性参数角度进行数值模拟指出,串联内阻越小、并联内阻越大、二极管反向饱和电流越小或二极管理想因子越大,适用CVT的区间就越宽。 | 张忠政 程晓舫 | 2014 | 中国电机工程学报2014，34，26： | 12 |
| 9 | Battery Technologies for Grid-Level Large-Scale Electrical Energy Storage显示文摘Grid-level large-scale electrical energy storage(GLEES) is an essential approach for balancing the supply–demand of electricity generation, distribution, and usage. Compared with conventional energy storage methods, battery technologies are desirable energy storage devices for GLEES due to their easy modularization, rapid response, flexible installation, and short construction cycles. In general, battery energy storage technologies are expected to meet the requirements of GLEES such as peak shaving and load leveling, voltage and frequency regulation, and emergency response, which are highlighted in this perspective. Furthermore, several types of battery technologies, including lead–acid, nickel–cadmium, nickel–metal hydride, sodium–sulfur, lithium-ion, and flow batteries, are discussed in detail for the application of GLEES. Moreover, some possible developing directions to facilitate efforts in this area are presented to establish a perspective on battery technology, provide a road map for guiding future studies, and promote the commercial application of batteries for GLEES. | Xiayue Fan Bin Liu Jie Liu Jia Ding Xiaopeng Han Yida Deng Xiaojun Lv Ying Xie Bing Chen Wenbin Hu Cheng Zhong | 2020 | Transactions of Tianjin University2020，26，2： | 11 |
| 10 | Superconducting magnetic energy storage for stabilizing grid integrated with wind power generation systems显示文摘Due to the interconnection of various renewable energies and adaptive technologies, voltage quality and frequency stability of modern power systems are becoming erratic. Superconducting magnetic energy storage(SMES),for its dynamic characteristic, is very efficient for rapid exchange of electrical power with grid during small and large disturbances to address those instabilities.In addition,SMES plays an important role in integrating renewable sources such as wind generators to power grid by controlling output power of wind plant and improving the stability of power system.Efficient application of SMES in various power system operations depends on the proper location in the power system, exact energy and power ratings and appropriate controllers. In this paper, an effort is given to explain SMES device and its controllability to mitigate the stability of power grid integrated with wind power generation systems. | Poulomi MUKHERJEE V. V. RAO | 2019 | Journal of Modern Power Systems and Clean Energy2019，7，2： | 11 |
| 11 | Requirement of ultra-high voltage GIS arrester to voltage gradient of metal-oxide varistor显示文摘The surge arrester with excellent protection characteristics would decrease the overvoltage level ap- plied on the power apparatus to reduce their insulation levels and manufacturing bottleneck. The arrester for the 1000-kV ultra-high voltage ac power transmission system is designed as tank-type structure. The field-circuit combination numerical method combining the three-dimensional finite element method with circuit is proposed to analyze the potential distribution of GIS arrester. By comparing several design schemes, the most effective method to improve the potential distribution along the varistor column is to increase the voltage gradient of the ZnO varistor. Synthesizing several influential factors, the suitable voltage gradient of ZnO varistor should be controlled to 435 V/mm, and the resulted nonuniform degree of the potential distribution along the varistor column inside the GIS arrester would be controlled smaller than 10%. The result in this paper provides the fundamental technical index for the study of the high voltage gradient ZnO varistors. | HE JinLiang HU Jun MENG BoWen ZHANG Bo ZHU Bin CHEN ShuiMing ZENG Rong | 2009 | Science China(Technological Sciences)2009，52，2： | 10 |
| 12 | Phillips-Heffron model for current-controlled power electronic generation unit显示文摘This paper presents a Phillips-Heffron model for the generation unit with current-controlled(CC) voltage source converter(VSC) as the interface. A concept of current angle is put forward for the CC-VSC, and the relationship between the current angle and the power angle is also quantified. Based on the current angle, a PhillipsHeffron model is established for the generation unit with CC-VSC, considering the dynamic of phase-locked-loop(PLL) in the weak grid. The model demonstrates that small-signal dynamics of the generation unit is similar to that of the traditional synchronous generator(SG) which is characterized by the electromechanical swing equations.Then the dynamics can be depicted by the famous inertia,synchronizing and damping coefficients. Small-signal stability of a CC-VSC-based single machine infinite bus system is analyzed by means of the traditional theory of power system. Based on the relationship between the current angle and the power angle, the Phillips-Heffron model of the CC-VSC is also used in stability analysis of multimachine power system, and parameter optimizations of the CC-VSC are also studied for stability improvement. | Shulong TAN Hua GENG Geng YANG | 2018 | Journal of Modern Power Systems and Clean Energy2018，6，3： | 10 |
| 13 | Effects of key factors of rotary triboelectrostatic separator on efficiency of fly ash decarbonization显示文摘On the basis of understanding the principle of rotary triboelectrostatic separation, dynamic analysis of charged fly ash particles aimed at determining the key factors and separation experiments to improve decarbonization efficiency had been carried out Variables of electrode plate voltage and corrected wind speed are the key factors which affect the decarbonization efficiency on the separation of fly ash, The results of separation experiments show that:(1) With the plate voltage increasing, the efficiency of decarbonization continuously rises and in its selected range, the optimal voltage level is 45 KV;(2) The corrected wind speed can impact the efficiency of decarbonization significantly: with the speed increasing, the efficiency of decarbonization shows a trend of first decline, then increase and decrease again, and in its selected range, the optimal speed is 2.0 m/s. This study is of significance for the improvement of rotary triboelectrostatic separation performance and its decarbonization separation efficiency. | Tao Youjun Zhang Ling Tao Dongping Xian Yushuai Sun Qixiao | 2017 | International Journal of Mining Science and Technology2017，27，6： | 10 |
| 14 | 8b/10b编码实现LVDS交流耦合传输中的直流平衡显示文摘LVDS在高速数据传输中得到了广泛应用,但在传输过程中存在交流耦合,使得连续出现的0或1信号传输会出现丢数、误码等问题。通过介绍直流平衡在交流耦合中的作用,采用8b/10b编码的方法,实现了直流平衡。同时说明了8b/10b编码的具体实现过程中的重点和细节。通过仿真和实际数据收发,证实了该方案的可行性、准确性,提高了LVDS数据传输能力。 | 刘泳锐 张彦军 刘龙飞 雷建胜 | 2012 | 科学技术与工程2012，20，35： | 10 |
| 15 | Modeling of bearingless permanent magnet synchronous motor based on mechanical to electrical coordinates transformation显示文摘A bearingless permanent magnet synchronous motor(BPMSM)has two sets of stator windings,torque windings and suspension force windings.By analyzing the flux linkage intersection between the two sets of windings,a method of transforming mechanical coordinates to electrical coordinates is put forward.According to this method,flux linkage equations and voltage equations of the two stator windings are derived.The electromagnetic torque equation of the BPMSM is derived based on the analysis of the role of Lorentz force in the BPMSM.After analyzing the mathematical formula of various sort radial forces in the BPMSM,a complete function of radial suspension forces for the BPMSM is obtained.Finally,an experimental system control diagram and some test results are discussed.This mathematical model provides a theoretical foundation for BPMSM simulation study,experiment waveform analysis and structure design. | ZHU HuangQiu CHENG QiuLiang WANG ChengBo | 2009 | Science China(Technological Sciences)2009，52，12： | 8 |
| 16 | Research on the Mechanism of Penetration Increase by Flux in A-TIG Welding显示文摘The mechanism of penetration depth increased by activating flux in activating tungsten inert gas (A-TIG) weldingwas studied by measuring the distribution of trace element Bi in the weld and monitoring the change of arc voltageduring A-TIG welding of stainless steel 0Crl8Ni9 with fluxes SiO2 and TiO2. The results show that the mechanismof penetration depth in A-TIG welding depends on the sort of flux used. The weld pool convection after coating theflux SiO2 and flux TiO2 is changed inversely compared with convectional TIG welding without flux. The arc voltageis increased by flux SiO2 whilst flux TiO2 does not have effect on the arc voltage. The reason of penetration depthincrease for SiO2 is due to the constriction of arc plasma and the change of surface tension gradient. The increaseof weld penetration depth with TiO2 only ascribes to the change of surface tension gradient. | Chunli YANG Sanbao LIN Fengyao LIU Lin WU Qingtao ZHANG | 2003 | Journal of Materials Science & Technology2003，19，z1： | 8 |
| 17 | Security region based real and reactive power pricing of power system显示文摘This paper develops a novel model and an algorithm of security region based real and reactive power pricing of power systems.In the proposed model,the reactive power production cost is represented as the opportunity cost.The static voltage stability region in the cut set power space(CVSR) and the practical dynamic security region(PDSR) in the injection power space are used to represent the constraints of voltage stability and transient stability,so that the consideration of this kind of constraints in the optimization becomes very easy.In the proposed algorithm,a decoupled optimization and iteration method of active power production cost and reactive power production cost is suggested.According to the K-T optimality conditions,the prices of active power and reactive power,and the different components corresponding to the concerned security constraints are derived.The components of spot prices can reflect the influence of different node power injections on each kind of security constraints,so that through the node price all of the participants in power market can be stimulated to take an active part in maintaining the system security.An illustrative example on the New England 10-genetator 39-bus System is used to demonstrate the proposed method. | YU YiXin1 & WANG YanJun1,2 1 Key Laboratory of Power System Simulation and Control of Ministry of Education,Tianjin University,Tianjin 300072,China 2 College of Mechanical and Electrical Engineering,Agriculture University of Hebei,Baoding 071001,China | 2008 | Science China(Technological Sciences)2008，51，12： | 7 |
| 18 | Power systems wide-area voltage stability assessment considering dissimilar load variations and credible contingencies显示文摘This paper reveals that the existing techniques have some deficiencies in the proper estimation of voltage stability margin(VSM) when applied to a power system with different load change scenarios.The problem gets worse when credible contingencies occur.This paper proposes a real-time wide-area approach to estimate VSM of power systems with different possible load change scenarios under normal and contingency operating conditions.The new method is based on an artificial neural network(ANN) whose inputs are bus voltage phasors captured by phasor measurement units(PMUs) and rates of change of active power loads.A new input feature is also accommodated to overcome the inability of trained ANN in prediction of VSM under N-1 and N-2 contingencies.With a new algorithm, the number of contingencies is reduced for the effective training of ANN.Robustness of the proposed technique is assured through adding a random noise to input variables.To deal with systems with a limited number of PMUs, a search algorithm is accomplished to identify the optimal placement of PMUs.The proposed method is examined on the IEEE 6-bus and the New England 39-bus test system.Results show that the VSM could be predicted with less than 1% error. | Bahram SHAKERIGHADI Farrokh AMINIFAR Saeed AFSHARNIA | 2019 | Journal of Modern Power Systems and Clean Energy2019，7，1： | 7 |
| 19 | Current-limiting characteristics of saturated iron-core fault current limiters in VSC-HVDC systems based on electromagnetic energy conversion mechanism显示文摘A common method to examine the current-limiting performance of saturated iron-core fault current limiter(SI-FCL) in high-voltage direct-current transmission based on voltage source converter(VSC-HVDC) systems is to solve differential equations based on the system fault transient characteristics and the equivalent inductance calculation equation. This method analyzes the fault current of the VSC-HVDC system in the time domain. However, it is computationally complex and cannot directly reflect the relationship between parameters and the currentlimiting effect of the SI-FCL.In this paper,the relationship between the magnetic flux density and magnetic field energy of the SI-FCL is analyzed. The energy exchange between the DC capacitor and the SI-FCL in the DC short circuit fault process is analyzed. From the perspective of electromagnetic energy conversion, the criterion for determining the current-limiting ability of the SI-FCL in the transient process is given based on the parameters of the SI-FCL and VSC-HVDC system. On this basis, the characteristics of the DC side fault current and the capacitor voltage when the SI-FCL has current-limiting ability are examined.Based on the parameters of the SI-FCL and VSC-HVDC system, a method for calculating the fault current peak value and capacitor voltage drop time is given. Finally, the accuracy of the analysis of the SI-FCL in the VSC-HVDC system based on the electromagnetic energy conversion mechanism is demonstrated through a case study and simulation results of the VSC-HVDC system with different SI-FCLs. | Botong LI Hanqing CUI Fangjie JING Bin LI Yichao LIU | 2019 | Journal of Modern Power Systems and Clean Energy2019，7，2： | 7 |
| 20 | Soft Fault Diagnosis for Analog Circuits Based on Slope Fault Feature and BP Neural Networks显示文摘Fault diagnosis is very important for development and maintenance of safe and reliable electronic circuits and systems. This paper describes an approach of soft fault diagnosis for analog circuits based on slope fault feature and back propagation neural networks (BPNN). The reported approach uses the voltage relation function between two nodes as fault features; and for linear analog circuits, the voltage relation function is a linear function, thus the slope is invariant as fault feature. Therefore, a unified fault feature for both hard fault (open or short fault) and soft fault (parametric fault) is extracted. Unlike other NN-based diagnosis methods which utilize node voltages or frequency response as fault features, the reported BPNN is trained by the extracted feature vectors, the slope features are calculated by just simulating once for each component, and the trained BPNN can achieve all the soft faults diagnosis of the component. Experiments show that our approach is promising. | 胡梅 王红 胡庚 杨士元 | 2007 | Tsinghua Science and Technology2007，12，S1： | 6 |
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